Our second post on the subject of tsukemono, Japanese pickles, introduces you to the subject of lacto-fermentation

Umeboshi

Soured ume plums are an absolute staple in Japan. The small, yellow fruit is part of the genus prunus and though referred to as a plum is more closely related to the apricot. The plums are salted and allowed to ferment before the addition of crumpled red perilla leaves and finally sun-dried

Lacto-Plums

Ume can sometimes be obtained in the West from Korean and Japanese stores when in season, but they are far from ubiquitous. Fortunately you can get fantastic results and comparable health benefits from standard plums. They will taste different. They’re a different fruit. But they are, in my mind, every bit as delicious.

Lacto-Fermentation

This is an old concept and much has been written about it. What follows is a simple summary for your convenience

What is it?

Fermentation is the microbial transformation of carbohydrates into either alcohol or lactic acid. Both are useful preservatives and have been used for millennia to preserve food

Lacto-fermented foods are pro-biotic, providing health-promoting micro-organisms and their bi-products to benefit not only gut function but also strengthen the immune system and even enhance your mood

Since most fruit and vegetables naturally contain lacto-bacteria, all you have to do is to provide the conditions for these to proliferate in preference to other potentially harmful bugs. Two conditions must be met:

Salt

While salt kills most bugs our friendly lacto-bacilli don’t mind a bit of it, though they do mind a lot. So for example, the addition of anything above 7% salt by weight will start to kill our lacto-friends and cure food, but not ferment it. 2-5% salt, on the other hand, will allow lacto-fermentation to get to work on virtually any fruit or vegetable transforming it into something to grace any meal, great or humble

No oxygen

Lactofermentation will only take place in anaerobic (no air) conditions. If your fruit or veg are directly exposed to oxygen they will soon develop mould and harmful bacteria and the whole batch will spoil

There are 3 commonly-used methods for preventing aerobic exposure

• Salting draws out water to create a brine in which you can keep your fruit immersed with the help of a weight – sliced sauerkraut is usually made this way
• Or you can mix a brine in which to immerse your veg – this is the method used for fermented whole cabbages, the leaves of which are used to make the Turkish stuffed-cabbage dish Sarma
• Large pieces of fruit such as plums do very well fermented inside a vacum-seal bag. These are very easily available and guarantee a scrupulously anaerobic environment. When fermenting plums this is, for me, the method of choice